Time controlled switch



June 27, 1933. w HOFFMANN 1,915,316

TIME CONTROLLED SWITCH Original Filed Nov. 3, 1931 v 2 Sheets-Sheet 1 Inventor V dummy:

June 27 1933. w HOFFMANN 1,915,316

TIME CONTROLLED SWITCH Original Filed Nov. 5, 1931 2 Sheets-Sheet 2 I Attorneys Patented June 27, 1933 PATENT OFFICE WILLIAM H. EOFFMANN, OF LOS ANGELES, CALIFORNIA TIME CONTROLLED SWITCH Application filed November 3, 1981, Serial No. 572,771. Renewed Kay 2, 1933.

My invention relates to time controlled switches and has particular reference to a time device for opening and closing an electrio circuit to which the device may be attached.

Many electrical devices are required to be operated for only a definite period of time, each day, so that it is desirable to have the device arranged to be automatically turned on at one time during the day and'turned ofl during another time of the day withoutthe necessity of an attendant for performing this operation.

An object of my invention is to provide a relatively simple device which will control an electric circuit to close the circuit at one time during a day and to open the circuit at another time during the day.

Another object of the invention is to provide a circuit controlling device which is timecontrolled to close a circuit at one time during the day and to open the circuit at another time during the day, in which the times at which the circuit is controlled may be readily adjusted.

Another object of my invention is to provide a device of the character described in the preceding paragraph in which the length of time the c. cuit is maintained either open or closed may be adjusted within very short limits of time.

Other objects of my invention will be apparent from a study of the accompanying drawings read in connection with the specifications, wherein Figure 1 is a front elevational view of a time controlled switching device constructed in accordance with my invention;

Fig. 2 is an enlarged detail elevational view of the switch and its operating mechanism with the cover removed;

Fig. 3 is a detailed sectional view taken along line IIIIII of Fig. l;

Fig. 4 is a detailed sectional view taken along line IV-IV of Fig. 3;

Fig. 5 is a detailed sectional view of one a of the circuit controlling cams and its adjusting means;

50 Fig. 6 is a detailed view of the electrical switch and the control means therefor employed in connection with my invention;

Fig. 7 is a detailed view of a cam -switch lever which may be employed .as a modified form of my invention; and

Fig. 8 is a detailed view of a still further modified form of switch operating lever and cam.

Referring to the drawings, I have illustrated my time controlled switch as comprising a suitable housing 1 having a front cdver plate 2 to the rear surface of which may be secured a suitable clockwork 3 (not shown in %etail )but indicated by the dashed outline in The clockwork mechanism 3 may be of the type generally employed for relatively small time keeping clocks, which comprises the usual spring and gear train mechanism for driving a shaft 4 upon which is secured a minute hand of a clock.

In my device, however, the minute hand is omitted and the usual gear 5 mounted upon and rotatable with the shaft 4 is intermeshed with an auxiliary gear 6. The gear 6 is illustrated as being mounted upon a stub shaft 7 and has rigidly secured thereto a small pinion -8 which in turn is meshed with a pair of spur gears 9 and 10 so that the gears 9 and 10 simultaneously may be rotated by what may be called the hour hand gear 5.

The gear 9 is illustrated as being mounted upon a sleeve 11, which is rotatable and slidable upon a continuation 4a of the shaft 4 of the clockwork so that a handle or thumb piece 12, mounted upon the extreme outer endof the sleeve 11, may be employed to draw the gear 9 toward the front cover 2 and thus out of meshing engagement, with the gear 8. When the gear 9 is so drawn outwardly'it may be rotated independently of the gear 8 and then pressed back to its normal position, such as is illustrated in Fig. 5, with its gear teeth in mesh with the teeth of the pinion 8. The gear 9 is illustrated as being normally pressed rearwardly into meshing position, as by means of a suitable compression spring 13.

The gear 10 is likewise mounted upona sleeve 14 provided with a thumb piece 15 to permit the gear 10 to be drawng outwardly out of mesh with the gear 8, and rotated independently of the pinion 8. If desired, the sleeve 14 may be guided by means of a stationary shaft 16 secured to one of the frame members 17 of the clockwork 3.

By referring particularly to Fig. 5, it will be observed that the gear 9 is provided with a forwardly extending pin 18 mounted near the periphery of the gear 9 in such position as to engage a switch operating lever 19 which in turn may be rotatably mounted upon the front frame 17 of the motor 3, as by means of a pivot pin 20. The gear 10 is similarly provided with a pin 21 also mounted near its periphery so as to also engage the switch operating lever 19.

By referring particularly to Fig. 2, it will be observed that the lever 19 is provided with a pair of cam surfaces 22 and 23, upon its lower edge, the surfaces in this form of the lever extending at an acute angle to the major axis of the lever 19. The portion of the lever 19 between the cam surfaces 22 and 2 is cut away as is illustrated at 24 so as to permit the lever 19 to be mounted closely adjacent the path of rotation of the pins 18 and 21. Thus as the pin 21 is rotated by its gear 10 it will'engage the cam surface 23 and press the right hand end of the lever 19 upwardly until the pin 21 moves past the'point of the cam surface 23. Similarly the rotation of the pin 18 by its gear 9 will cause it to engage the cam surface 22 to raise the lefthand end of the lever until the pin passes the point of the cam surface 22. Thus the extreme left-hand end of the lever 19 will be alternately raised and lowered by the respective engagement of the pins 21 and 18 with their cam surfaces.

The extreme left hand end of the lever 19, Figures 7 and 8, is illustrated as having a bearing surface 25 formed thereon to engage a roller 26 formed of insulating material rotatably mounted in a bracket 27, which is in turn mounted upon or formed integrally with one leaf 28 of a switch 29. The switch 29 also comprises a second leaf 30, both of the leaves being rigidly secured to the frame l7 of the clockwork, as by means of a screw '31, suitable insulation 32 preventing eleptrical contact between the screw and the leaves, and also insulating the leaves 28 and from each other.

The upper end of the leaf 39 is illustrated as being provided with a contact 33 which cooperates with a contact 34 mounted upon the switch leaf 28 so that the normal results of the switch leaf 28 will maintain contacts and 34 in engagement with each other to close an electrical connection between the switch leaves 28 and 30. However, when the bearing surface 25 of the switch lever 19 is moved downwardly, the leaf 28 will be moved outwardly away from the leaf 30 to separate the engagement of contacts 34 and 33 to thus open a circuit which may be controlled by the switch 29.

The switch 29 may be connected in an suitable circuit which it is desired to contro as by means of connecting the switch leaves 28 and 30 in series relation between a source of electrical supply and the device which is to be controlled.

By referring particularly to Fig. 1, it will be observed that current may be supplied to a radio 35, or other device which it is desired to control, as by means of connecting the same to a pair of conductors 36 and 37 which terminate in the usual block connection 38. The block connection 38 may be inserted in a suitable. block receptacle 39 which in turn bears block fingers 40 and 41 which may in turn be inserted in the usual current supply outlet generally employed in electrical wir- 'ing systems in buildings and the like. However, a block 40 may be suitably connected, as by means of a conductor 42, to that part of the receptacle 39 which is connected by one of the contacts of the block 38 while the other block 41 of the receptacle 39 is connected by nieansof a conductor 43 tp the switch leaf 28 of my switching device, a return conductor extending from switch leaf 30 by way of conductor 44 to the opposite terminal 45 of the receptacle 39 which is in turn engaged by the second contact member of the block 38. Thus the circuit'for the radio or other device to be controlled extends from the source of supply through the contacts of switch'29 and then to the radio 35 or other device and then back to the source of supply.

Hence upon every operation of the lever 19 to move the bearing surface 25 downwardly the circuit will be broken, while similarly, when the bearing surface 25 is moved upwardly, the circuit will be re-established to furnish current to the radio or other device which is desired to be controlled by my time control switch.

By referring particularly to Fig. 1, it will be observed that the finger pieces 12 and 15 are respectively provided with an indicating pointer 46 and 47, which are arranged to r0- tate with the sleeves and gears with which the respective finger pieces are associated. Thus the front cover 2 of the switch may be provided with a section calibrated, as is indicatcd at 48, into hours of a day. The location of the pointer 46, relative to the sleeve 11, should be so selected that when the pointer is on the starting point or zero calibration {indicated by the reference character 0), the pin 18, associated with the gear 9, will just have cleared its cam surface 22 on the switch operating lever 19. That is, when the pointer 46 is on the zero point, the switch 29 Ill will have just been closed by the operation of that'when this pointer is in its zero position indicated by the reference character N, the pin 21, associated with gear 10, will have just cleared its cam surface 23 and will thus have operated lever 19 to its downward position. That is, at this time the switch lever has been moved to such position as will have just opened the contacts of the switch 29.

By referring particularly to Fig. 4, it will be observed that the ratio of the gearing between the pinion 5 and its gear 6,and between the pinion 8 and the gears 9 and 10, is suitably selected so that the gears 9 and 10 will be rotated through one complete revolution during a day or during a pre-selected portion of a day, ifdesired. For example, the gearing should be such that twenty-four rotations of the pinion 5 will cause one complete rotation of the gears 9 and 10. Thus, independent of the time of day, my device may set to close the switch to start the device by drawing out the finger piece 12, rotating the same and setting it back with the gear 9 in engagement with its pinion 8 and with the point 46 pointing to a calibration'spaced from. the zero point in the cal bration 48 in the direction of the arrow 49, the desired number of hours or fractions thereof desired to elapse before the device 35 is to be operated. That is, assuming that the time of the day at which the device is set is noon, and it is desired to turn on the device 'at 4 oclock, the pointer 46 may be set two calibrations away from the zero point; thus as soon as four hours have elapsed, the rotation of the gear 9 by the clockwork will be such as to cause the pin 18 v to engage and operate the lever 19 to close the switch. If desired, intermediate calibrations may be provided so that the pointer 46 may be set to turn the switch on at the expiration of fifteen minutes, thirty minutes,

forty-five minutes, or other fractions of an hour, or at any number of hours and fractions thereof, which may be desired.

In like manner, the pointer 47 may be set at opposite any of its calibrations corresponding to the length of time desired to elapse before the switch 29 will be opened. That is, if the pointer 47 is set four calibrations in advance of its zero position N, eight hours will elapse before the switch isopen, or, in other words, the switch will be opened four hours after it has been closed.

By suitably selecting the position of the pointers 46 and 47, the device 35 may be so controlled that it will start at any timeduring the day, and may be stopped at any other time during the day.

By referring particularly to Fig. 2, it will be observed that the shape of the cam surfaces22 and'23 is such that the switch 29 is'operated only upon the passage of the'pins past the extreme-point of the cam surfaces, and since these points are relatively nearer, the limits within which the switch 29 may be turned ofi and turned on, or vice versa, may

be relatively small. That is, the pins 18 and insure that the lever 19 will remain in the switch closing or switch opening position durin the interval between the contact by the pins 18 and 19, a projection 25a may be provided upon the bearing surface 25 to form a depression into which theroller 26 extends and whereby it may be held in the position to which it is moved.

By referring particularly to Fig. 7, it will be observed that a modified form of the switch operating lever 19 may be employed, this form of the device having cam surfaces 22a and 23a which substantially parallel the major axis of the lever 19. Again however the points 50 and 51 of the cam, at which the switch will be operated by the lever, are relatively minute so that close adjustment of the time of operation of the switch to on and i then to off position, may besmall.

Referring particularly to Fig. 8, a still further modified form of the switch operating lever 19 is shown, in which the cam sur' faces are illustrated at 22b and 23b somewhat similar to the surfaces 22a and 23a 1 shown in Fig. 7. However, the cam surfaces in this instance are supplemented by spring members 220 and 230 which are normally in the position illustrated in Fig. 8, so that the engagement of these springs by the pins 18 and 21, respectively, will tend to move the switch lever 19. However, if the pointers I 46 and 47 are set for close adjustment, for example if the device is set to turn on at one time and off fifteen minutes thereafter, the pin 21 will engage its cam surface23 prior to the time at which the pin 18 will have moved away from the cam surface 226.

ticularly desirable since this latter movement a will be extremely rapid, a desirable feature in the operation of a switch since it will sepa-.

rate the electrical contacts rapidly and thus prevent arcingbetween them.

If desired, he usual setting mit manual rotation of the pinion 5 while a winding mechanism is illustrated 1n dotted lines at 54 as constituting the usual winding ,7 W

finger piece 53 may be provided for the clockwork 3 to pe'r- 25 While I have illustrated and shown the preferred embodiment of my invention, it is to be understood that I do not wish to be limited to the details of construction shown 5 and described herein, except as defined in the appended claims.

I claim:

1. in a time controlled means for opening and closing a switch, a pair of switch conio tacts, a switch operating lever for actuating said contacts to open or closed position, a cam surface on said lever forming substantially a point, a cam engaging means rotatably mounted relative to said cam surface for engaging and operating said lever when said engaging means passes said point, driving means for said cam engaging means rotating; at a predetermined speed, gearing con ne'cting said cam engaging means and said 29' driving: means, and means for disconnecting said gearing to permit rotation of said cam engaging means independentof the driving means to adjust the time at which said cam engaging means will actuate said leveix 2. in a time controlled means for opening and closing a switch, a pair or switch contacts, a switch operating lever for actuating said contacts to open or closed position, a cam surface on said lever forming 3Q substantially a point, a cam engaging means rotatably mounted relative to said cam face "for engaging and operating said lever when said engaging means passes said point, driving means for said cam engaging means rotating at a predetermined speed, gearing connecting said earn engaging means and said driving means, means for disconnectingsaid gearing permit rotation of said A cam engaging;- nieans independent or" the driving means to adjust the time at which said cam engaging means will actuate said. lever, and resilient means for interengaging said cam surface andsaid cam engaging means to operate said lever with a rapid mo- 5 tion.

Signed at Los Angeles, California, this 27th day of October, 1931.

WILLIAM H. HOFFMANN. 

